PROC. ENT. SOC. WASH., VOL. 22, NO. I, JAN., 1920. 



lished data on our fauna. Drury (1878) 1 published a brief note 

 on two species of Bothrideridae, Bothrideres geminatus Say. and 

 Erotybothris exaratus Melsh., stating that they spin cocoons. 

 Stebbing (1914) 2 likewise calls attention to this fact (on an Indian 

 species) and states that the larvae are predaceous. 



The described European species all belong to the Colydiidae. 

 In several cases it is noted that the larvae are predaceous but 

 all species here described and reared are purely feeders on de- 

 caying vegetable matter. It is possible that the genus Colydiuvn 

 may be predaceous basing the supposition on the habits of the 

 adult. 



COLYDIIDAE. 



In the family Colydiidae the genera Auloniwn, Ditorna, Phloe- 

 onemus, N ematidium and Synchita have been studied. They may 

 be characterized as follows: 



Elongate, cylindrical to subcylindrical; legs well developed, five jointed 

 coxae conical, well separated, tarsi claw-like (no tarsal claws) ; head extended 

 from prothorax, nearly hypognathous, labrum well defined, mouth parts 

 deeply retracted; hypopharynx, which is lightly chitinized, strongly con- 

 nected by arm of hypostoma; inner side of stipes free to near base; cardo 

 transverse, obliquely articulating with stipes; maxillary sclerite large, 

 cushioned; gula well defined, forming a strong support between ventral epi- 

 cranial halves; mandibles having well developed molar part, bidentate at 

 apex and no retinaculum ; antennae contiguous to mouth frame, three-jointed 

 (except Nematidium) with supplementary joint; pre and posthypopleural 

 chitinization of thorax very narrow; presternum of prothorax large, subtri- 

 angular; presternal fold of meso- and meta thorax well defined; cerci of two 

 rigid recurved spines, usually with a sac-like depression between; tenth seg- 

 ment wart-like, ventral; spiracles bifore, mesothoracic on presternal ring. 



TAXONOMIC POSITION OF THE COLYDIIDAE. 3 



The larvae of the Colydiidae must be regarded as belonging 

 to the so-called Heteromerous series. In fact, it is difficult to 

 find characters that will separate them from certain of these 

 families. The retraction and structure of the mouth parts is 

 common to a large series of families beginning with the Cucujidae 

 and Cryptophagidae. It appears in the Mycetophagidae, By- 

 turidae and all the Heteromerous families except the Mordellidae, 



1 Drury, Charles. Canadian Ento. Vol X, p. 210, 187s. 



2 Indian Forest Insects. London, 1914 E. P. Stebbing, p. 334. 



3 The following taxonomic discussion is based on a joint study of the 

 characterization of Coleopterous larvae undertaken by A. G. Boving and 

 F. C. Craighead. 



